Shell Rotella T6 Full Synthetic 5W40 Heavy-Duty Diesel Engine Oil, 18.9L – 550046217
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Shell Rotella T6 Full Synthetic 5W40 Heavy-Duty Diesel Engine Oil – 18.9L | Part #550046217
Rotella T6 is Shell’s full synthetic heavy-duty diesel engine oil, representing the top tier of the Rotella line. The 5W40 multi-grade formulation provides excellent cold-start protection down to low temperatures while maintaining a strong oil film at high operating temperatures — making it a year-round choice for demanding diesel applications. The 18.9L (5 US gallon) jug is the right size for shops and operators who want the performance of full synthetic without stepping up to a drum.
Energized Protection® Formula
Rotella T6 uses Shell’s proprietary Energized Protection® technology, which goes beyond conventional wear protection to actively control the three primary causes of diesel engine degradation:
- Acid control — neutralizes combustion acids before they can attack engine surfaces
- Deposit control — keeps pistons, rings, and combustion chambers clean for sustained efficiency
- Wear protection — advanced synthetic base stock and additive package reduces metal-to-metal contact under high load
Key Features
- Full synthetic formulation — superior thermal stability, oxidation resistance, and low-temperature performance compared to conventional or synthetic-blend oils
- SAE 5W40 multi-grade — excellent cold-start flow and high-temperature viscosity retention for year-round use
- Better fuel economy — reduced internal friction contributes to measurable fuel savings in heavy-duty applications
- Compatible with modern emissions systems — suitable for engines with EGR, DPF, and SCR systems where the oil specification permits
- Backward compatible — suitable for older diesel engines as well as modern low-emission powerplants
- 18.9L jug — 5 US gallons, practical for multi-quart fills or keeping a full season’s supply on hand
Specifications
- Grade: SAE 5W40 (full synthetic)
- Application: Heavy-duty diesel engines (on-highway, off-highway, marine auxiliary, stationary)
- Size: 18.9L (5 US gallons)
- Part number: 550046217
Parts Desk Insights
Best use case: Rotella T6 5W40 is the right choice when maximum protection is the priority — high-hour engines, turbocharged diesel powerplants, cold-climate operation, or any application where extended drain intervals are desired and the OEM approves a full synthetic 5W40. The 18.9L jug is particularly practical for operators servicing larger diesel engines (8+ quart capacity) or for shops that want to keep a full synthetic option stocked without committing to a drum. For the same T6 formulation in a smaller 5L bottle, see the Shell Rotella T6 Full Synthetic 5W40, 5L – 550046214. If your application calls for a conventional or synthetic-blend 15W40 instead of a full synthetic 5W40, the Rotella T4 Triple Protection is available in 5L (3/case), 9.5L (2/case), 18.9L (2/case), and 208L drum formats.
Note: Always confirm your engine manufacturer’s oil specification — viscosity grade, API service category, and any OEM approvals — before ordering. Not all diesel engines approve a 5W40 full synthetic; verify your engine’s requirement in the service manual.
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 3–4 business days.
Special-order items: timeline confirmed after order.
Returns & warranty
Returns & Satisfaction Guarantee
We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.
If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.
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Item must be in new, unused condition
Product must be in its original packaging
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Packaging must be undamaged and suitable for resale
Important:
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